A visit to the nest takes very little time and you could easily miss it. Leave them alone! Mom and Dad are still around if you don't keep them away. What makes you think the Mom is dead?

Try to find the number for a wildlife rehab center close to you…even if that's 200 miles away. They may know of rehabbers closer to you and can tell you what to do.

If the mom sees you it will not come near the nest. Stay away and watch with binoculars and leave Nature alone even if those babies become fox poo it will be Natures way of recycling.

http://www.instructables.com/id/How-to-R...

So there was a hummingbird nest in our yard and i was keeping an eye on it from a while i recently noticed that their mother was not coming to feed them i kept observing them for a hour or 2 but she didn't came until i found out that their mother is dead so i wanna know that how to take care of them, they are still very young.

There is no vet center or animal care center here so i can't rely on anyone.